Conventionally, in the optimum shape design of the cushioning material used in the cushioning packaging, a cushioning thickness and a pressure receiving area are determined so as to satisfy mechanical design conditions based on cushioning performance data of a plate-shaped cushioning material. After the cushioning material shape is formed so as to satisfy the mechanical design conditions, decision of moldability and calculation of manufacturing cost are performed. The design is repeatedly reviewed until the optimum shape is obtained under the mechanical design conditions.
With reference to the conventional structure optimizing method, Japanese Patent Application Laid-Open (JP-A) No. 9-44551 (Patent Document 1) discloses a method, in which pieces of CAD (Computer Aided Design) data of various cushioning materials for packaging products is previously stored in a library group, and the cushioning member is designed by appropriately selecting the CAD data from the stored pieces of CAD data according to the target cushioning member.
JP-A No. 2002-7487 (Patent Document 2) discloses a method in which a minimum value of a cushioning material volume is detected to determine the optimum shape of a structure based on the cushioning material shape whose rigidity is maximized when the cushioning material volume is the minimum volume. In the minimum value of the cushioning material volume, the maximum deceleration of contents satisfies a design tolerance,
JP-A No. 2000-331035 (Patent Document 3) discloses a method in which customer's component requirements, such as the maximum weight, minimum lifetime, minimum reliability, minimum strength, durability, a minimum environmental operating condition, an adaptive value to reference, and cost of a design target, are set as parameters.
JP-A NO. 2001-297118 (Patent Document 4) discloses a method, in which the optimum shape of the cushioning material is obtained by inputting an optimum area, and the cushioning material shape with a topology (phase and morphology) change caused by adding/eliminating a rib or a boss can be optimized in a short time.
JP-A No. 3-224063 (Patent Document 5) discloses a method an optimum model satisfying design requirements is designed by inputting cushioning material design requirements, an early-stage shape, applicable scope of design parameter, and a boundary condition.
Patent Document 1: JP-A No. 9-44551
Patent Document 2: JP-A No. 2002-7487
Patent Document 3: JP-A No. 2000-331035
Patent Document 4: JP-A No. 2001-297118
Patent Document 5: JP-A No. 3-224063